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Navigating "tip fog": embracing uncertainty in tip measurements
Jeremy M Beaulieu1, Brian C O'Meara2
1Department of Biological Sciences, University of Arkansas, Fayetteville, AR, United States.
Evolution; International Journal of Organic Evolution
|April 3, 2025
Summary
Ignoring "tip fog," or variation in evolutionary data, leads to inaccurate evolutionary models and biased rate estimates. Accounting for this variance is crucial for precise phylogenetic comparative analyses.
Area of Science:
- Evolutionary Biology
- Phylogenetics
- Quantitative Biology
Background:
- Evolutionary processes generate inherent variation, crucial for natural selection.
- Overlooking variation in biological data leads to inaccurate models and parameter estimates.
- Uncertainty in biological data extends beyond measurement error, including various sources of variance.
Purpose of the Study:
- To introduce and define "tip fog" as the variance between modeled evolutionary processes and recorded data.
- To demonstrate the critical impact of tip fog on comparative models in evolutionary biology.
- To provide methods for estimating tip fog and assess its importance in phylogenetic analyses.
Main Methods:
- Redevelopment of methods for estimating variance associated with tip fog.
- Simulations used to assess the feasibility and significance of tip fog estimation.
- Analysis of the impact of tip fog on continuous, discrete, and diversification models.
Main Results:
- Neglecting tip fog significantly biases estimates of evolutionary rates.
- Higher levels of tip fog result in greater inaccuracies in rate estimations.
- Tip fog influences the selection of appropriate evolutionary models.
Conclusions:
- Accounting for tip fog is essential for accurate evolutionary rate estimation.
- Model selection in phylogenetics is critically affected by the presence of tip fog.
- Addressing tip fog improves the reliability of comparative methods in evolutionary biology.
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